1. Field of the Invention
The present invention relates to a magnetoresistive film for use in a read head, for example, of a magnetic recording medium drive or storage device, such as a hard disk drive (HDD) and a magnetic tape drive.
2. Description of the Prior Art
A magnetoresistive film is widely used in a read head incorporated in an HDD, for example. When magnetic data is to be read in the HDD, a sensing current is supplied to the magnetoresistive film. When the magnetoresistive film is exposed to the magnetic field leaking from a recording medium, voltage variation appears in the supplied sensing current. Binary data can be discriminated from each other based on the voltage variation. A larger amplitude of the voltage variation ensures a constant precise determination of magnetic data read out of a recording medium. An increased current value of the sensing current leads to an enlarged amplitude of the voltage variation.
In the field of HDDs, for example, a magnetoresistive film is required to get further reduced in size to achieve an increased recording density. A magnetoresistive film of a reduced size tends to suffer from an excessive increase in the temperature due to its electric resistance. The increased temperature correspondingly induces a further increase in the electric resistance of the magnetoresistive film, resulting in deteriorated characteristics as well as destruction of the magnetoresistive film. An enlarged voltage variation should accordingly be achieved in a magnetoresistive film for use in a read head without suffering from an excessive increase in the temperature.